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Chinese chemical Letters 1995年第9期6卷 747-750页

作者： Chun Lin MA Xi Yan LU and Yong Xiaug MA(Department of chemistry, liaocheng Teachers {2..liaocheng 2.2.59)(Shanghai Institute of Organic chemistry, Academia Sinica.Shanghai) (Department of chemistry, Lanzhou university, Lanzhou 730000) liaocheng Teachers Coll Dept Chem Liaocheng 252059 Peoples R China Chinese Acad Sci Shanghai Inst Organ Chem Shanghai 200032 Peoples R China Lanzhou Univ Dept Chem Lanzhou 730000 Peoples R China

Abstract: The 1E. 3E-dienyldiethyl phosphonate and 1E, 3E-dienyldiphenyl phosphine oxide were synthesized via isomerizationofalkynyldiehtyl phosphonate and alkynydiphenyl phosphine oxide effected by tributyl-phosphine

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Biological decomposition of Na_2._2._3 into sulfur by a newly isolated facultative thermophilic alkaline desulphuricant strain

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Science china chemistry 2009年第2期52卷 226-230页

作者： ZHANG JianBin1,ZHANG Tong2.MA Kai2.ZHANG PengYan2.LI Qiang2.& WEI XiongHui1 1 Department of Applied chemistry,college of chemistry & Molecular engineering,Peking university,Beijing 100190,china 2.college of chemical engineering,Inner Mongolia university of Technology,Huhhot 010051,china 1. Department of Applied chemistry College of Chemistry & Molecular Engineering Peking University Beijing 100190 China 2. college of chemical {2.ing Inner Mongolia University of Technology Huhhot 010051 China

A facultative thermophilic alkaline desulphuricant strain named GDJ-3 was isolated from neutral soils,enriched on sulfur synthetic medium,and detected in previous *** and chemotax-onomic analyses and 16s RNA gene sequencing showed that the strain was in good agreement with Alpha proteobacterium sp.(97%) and ochrobactrum sp.(98%).The regenerative processes of the solu-tion containing sulfur compounds(SCS) from the strain through an orthogonal test were investigated to get the optimum regenerative *** results showed that regenerative temperature,air flow,and stirring speed of the agitator were the main three variables influencing the regenerative processes of the *** optimum regenerative efficiency of the SCS from the strain was obtained when tem-perature,air flow,and stirring speed of the agitator were 318.2.K,3.0 L/min,and zero r/min,*** this condition,when the cell concentration of the strain was adjusted to 107/mL,the concentra-tions of Na2.2.3 and Na2. in the SCS decreased from 112.68 g/L to 96.88 g/L and from 0.87 g/L to 0.11 g/L in 9.5 ***,XRD spectrum shows that sulfur was formed in the regeneration *** results suggest that the strain has potential application to the regeneration of the industrial so-lution containing sulfur compounds.

关键词： bio-desulfurization thermophiles optimization biocomposition orthogonal test

A novel four-component reaction involving ring-opening/recyclization of 1,3-thiazolidinedione

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Science china chemistry 2010年第4期53卷 863-868页

作者： SUN Jing, XIA ErYan, ZHANG LiLi & YAN ChaoGuo college of chemistry & {2. engineering, Yangzhou university, Yangzhou 2.5002. china 1. college of chemistry & {2. engineering Yangzhou University Yangzhou 225002 China

The multicomponent reactions of 1,3-thiazolidinedione, malononitrile, aromatic aldehydes and α-phenylethylamine or β-phenylethylamine in acetonitrile at room temperature produce dihydrothiophene ureidoformamide derivatives in moderate yields through a domino ring-opening/recyclization reaction of 1,3-thiazolidinedione. On treatment with DDQ, dihydrothiophenes are dehydrogenated to convert efficiently to thiophenes in the mild condition.

关键词： multicomponent reaction ring-opening recyclization dihydrothiophene thiazolidinedione

Adsorption Breakthrough of Benzene in the Fixed Bed of Modified Activated Carbon under Different Humidity Conditions

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Journal of Wuhan university of Technology(Materials Science) 2010年第3期25卷 499-503页

作者：李晶 college of chemistry and {2. engineering Zhongkai University of Agriculture and Engineering

The breakthrough curves of benzene and water on modified activated carbons（ACs） were ***-programmed desorption（TPD） experiments were conducted to measure the TPD curves of benzene and water on modified and unmodified ACs and to estimate the activation energy for the desorption of benzene on the modified *** with unmodified ACs,two modified ACs were prepared by using two different types of silane,designated by KH560 and *** results showed that the activation energy for the desorption of benzene on KH560/AC and 1706/AC was higher than that on unmodified *** addition,the activation energy for the desorption of water on KH560/AC and 1706/AC was lower than that on unmodified *** breakthrough curves of benzene obtained from the experimental observations under different humidity conditions were compared with the results of the TPD *** results show that the modified ACs are less affected by water,whereas the unmodified ACs are more affected by water,indicating that surface modification by organosilane compounds can improve the adsorption of benzene on the activated carbo,which weakens the adsorption of water.

关键词： activated carbon benzene water TPD activation energy of desorption breakthrough curves

Size effect of fullerene cages and encaged clusters in M3N@C2.

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Science china chemistry 2009年第5期52卷 584-589页

作者： GAN LiHua School of chemistry and chemical {2.ing, Southwest university, Chongqing 400715, china School of chemistry and chemical {2.ing Southwest University Chongqing 400715 China

Based on the calculated findings that the sizes of encaged clusters determine the structures and the stability of C80-based trimetallic nitride fullerenes (TNFs), more extensive density functional theory calculations were performed on M3N@C68, M3N@C78 and M3N@C80 (M=Sc, Y and La). The calculated results demonstrated that the structures and stability undergo a transition with the increasing of the sizes of the cages and clusters. Sc3N is planar inside the three considered cages, Y3N is slightly pyramidal inside C68-6140 and C78-5 and planar inside I h C80-7, however, La3N is pyramidal inside all the three cages. Those cages with pyramidal clusters inside deformed considerably, compared with their parent cages. In these cases, the bonding of metallic atoms toward the cages does not play an impor-tant role, and the encaged cluster tends to be located inside the cages with the largest M-M and M-C distances so that the strain energy can be released mostly. These calculations revealed the size effect of fullerene cages and encaged clusters, and can explain the position priority of M3N inside fullerene cages and the differences in yield of M3N@C2..

关键词： trimetallic nitride fullerenes (TNFs) density functional theory (DFT) size effect stability

Kinetics and mechanism of the reaction between thiourea and iodate in unbuffered medium

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Science china chemistry 2004年第6期47卷 480-487页

作者： WANG Shun1,2. LIN Juanjuan1, CHEN Fan1, HU Maolin1, HU Xingen1, HAN Yiping1 & GAO Qingyu2.1.Department of chemistry and Material Science, Wenzhou Normal college, Wenzhou 32.02.,{2. 2. college of chemical engineering,{2. university of Mining and Technology, Xuzhou 2.1008,{2. 1. Department of chemistry and Material Science Wenzhou Normal College 325027 Wenzhou China 2. college of chemical {2.ing China University of Mining and Technology 221008 Xuzhou China

The reaction between iodate and thiourea has been studied in an unbuffered acidic medium. In excess iodate the reaction shows not only oligooscillations in pH, Pt potential and the concentration of iodide ion, [I?], but also an initial induction period which has the linear relation with initial pH. At the end of the induction period, [I?] decreases sharply and a yellow coloration (due to iodine) appears transiently. While in excess thiourea iodine is produced and finally con- sumed, leaving milky deposits (due to sulfur) at the end of the reaction. The induction period from the start of the reaction to the maximum of [I2. is also directly proportional to initial pH. A 14-step mechanism, including a H+-mediated preequalibrium, Dusman reaction, iodine-sulfur reactions and sulfur-sulfur reactions, is proposed. Computer simulations using this mechanism give good agreement with experiments.

关键词： oligooscillations, pH dynamics, thiourea, iodate, complex reaction mechanism, dynamic simulation.

Controlled synthesis and magnetic properties of Fe_3O_4 walnut spherical particles and octahedral microcrystals

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Science china(Technological Sciences) 2008年第11期51卷 1911-1920页

作者： JIAO Hua1,2.& YANG HeQing1 1 Key Laboratory of Macromolecular Science of Shaanxi Province, School of chemistry and Materials Science, Shaanxi Normal university, Xi’an 710062.{2. 2.Department of chemistry and chemical engineering, Weinan Teachers university, Wei nan 714000,{2. Key Laboratory of Macromolecular Science of Shaanxi Province School of Chemistry and Materials Science Shaanxi Normal University Xi’an 710062 China Department of chemistry and chemical {2.ing Weinan Teachers University Wei nan 714000 China

Magnetite Fe3O4 walnut spherical particles and octahedral microcrystals were suc- cessfully synthesized from K4 [Fe (CN) 6], K3 [Fe (CN) 6] and NaOH reagents via a simple hydrothermal process. And the uniform morphology of octahedral micro- crystals was obtained in the presence of ethylene glycol. The morphology and structure of products were characterized by powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the Fe3O4 walnut spherical particles and octahedral microcrystals were single crystals with the face-center cubic structure and with size distributions from 2.2.to 8.6 μm and 1.6 to 12.5 μm, respectively. Their magnetic properties were detected by a vibrating sample magnetometer at room temperature. The walnut spherical parti- cles exhibited a ferromagnetic behavior with the coercive force (Hc), saturation magnetization (Ms) and remanent magnetization (Mr) being 150.57 Oe, 97.634 and 12.05 emu/g, respectively. For the octahedral microcrystals they were 75.2. Oe, 101.90 and 6.69 emu/g, respectively. Different sizes of walnut spherical particles were controlled synthesized through adjusting the NaOH concentration. It was found that ethylene glycol molecules have a significant effect on the formation of Fe3O4 octahedra. A possible mechanism was also proposed to account for the growth of these Fe3O4 products

关键词： a hydrothermal route Fe3O4 walnut spherical particles octahedral microcrystals magnetic property

Thermal oxide synthesis and characterization of Fe_3O_4 nanorods and Fe_2._3 nanowires

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Science china chemistry 2009年第5期52卷 599-604页

作者： JIAO Hua1,2.& YANG HeQing1 1 Key Laboratory of Macromolecular Science of Shaanxi Province, School of chemistry and Materials Science, Shaanxi Normal university, Xi’an 710062.{2. 2.Department of chemistry and chemical engineering, Weinan Teacher’s university, Weinan 714000,{2. 1. Key Laboratory of Macromolecular Science of Shaanxi Province School of Chemistry and Materials Science Shaanxi Normal University Xi’an 710062 China 2. Department of chemistry and chemical {2.ing Weinan Teacher’s University Weinan 714000 China

Fe3O4 nanorods and Fe2.3 nanowires have been synthesized through a simple thermal oxide reaction of Fe with C2.2.4 solution at 2.0-600℃ for 1 h in the air. The morphology and structure of Fe3O4 nanorods and Fe2.3 nanowires were detected with powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The influence of temperature on the morphology development was experimentally investigated. The results show that the polycrystals Fe3O4 nanorods with cubic structure and the average diameter of 0.5-0.8 μm grow after reaction at 2.0-500℃ for 1 h in the air. When the temperature was 600℃, the samples completely became Fe2.3 nanowires with hexagonal structure. It was found that C2.2.4 molecules had a significant effect on the formation of Fe3O4 nanorods. A possible mechanism was also proposed to account for the growth of these Fe3O4 nanorods.

关键词： thermal oxide process nanorods nanowires C2.2.4 iron sheet

Theoretical study of bifurcated bent blue-shifted hydrogen bonds CH_2.Y

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Science china chemistry 2008年第7期51卷 623-631页

作者： LI AnYong School of chemistry and chemical {2.ing, Southwest university, Chongqing 400715, china School of chemistry and chemical {2.ing Southwest UniversityChongqing 400715China

Ab initio quantum chemistry methods were applied to study the bifurcated bent hydrogen bonds Y… H2.Z (Z = O, S, Se) and Y…H2.Z2.(Z = F, Cl, Br) (Y = Cl-, Br-) at the MP2.6-311++G(d,p) and MP2.6-311++G(2.f,2.) levels. The results show that in each complex there are two equivalent blue-shifted H-bonds Y…H—C, and that the interaction energies and blue shifts are large, the energy of each Y…H—C H-bond is 15-2. kJ/mol, and Δr(CH) = -0.1 - -0.5 pm and Δv(CH) = 30 - 80 cm-1. The natural bond orbital analysis shows that these blue-shifted H-bonds are caused by three factors: large rehybridization; small direct intermolecular hyperconjugation and larger indirect intermolecular hy- perconjugation; large decrease of intramolecular hyperconjugation. The topological analysis of elec- tron density shows that in each complex there are three intermolecular critical points: there is one bond critical point between the acceptor atom Y and each hydrogen, and there is a ring critical point inside the tetragon YHCH, so these interactions are exactly H-bonding.

关键词： bifurcated bent H-bonds blue-shifted H-bonds topological property of electron density intramolecular hyperconjugation

Resonance Rayleigh scattering study of the interaction of bleomycinA_5 with nucleic acids and its analytical application

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Science china chemistry 2007年第5期50卷 629-637页

作者： LIU JiangTao1,2. LIU ZhongFang1 & LIU ShaoPu1 1 School of chemistry and chemical {2.ing, Southwest university, Chongqing 400715, china 2.Department of chemistry, Fuling Normal university, Chongqing 408000, china School of chemistry and chemical {2.ing Southwest UniversityChongqing400715China Department of chemistry Fuling Normal UniversityChongqing 408000China

The interaction of bleomycinA5 with nucleic acids has been investigated byusing resonance Rayleigh scattering (RRS),molecular absorption and fluorescence *** resultshows that in near pH 2.2.buffer medium and absence of any metal ions,nucleic acids are capable ofbinding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensityand result in batho-chromic and hyperchromic molecular absorption of nucleic acids and fluorescencequenching of *** RRS spectral characteristics for the binding products of bleomycinA5with various DNA and RNA are similar,and the maximum RRS peaks are at 301 nm for ctDNA and sDNA,370nm for hsDNA,310 nm for RNAtypeVI and RNAtypelll,*** increments of RRS intensity aregreatly different in which DNA enhances greatly and RNA enhances *** this work,the optimumconditions of the interaction and some influencing factors have been *** reactionmechanism and a binding model for the interaction of BLMA5 with the nucleic acids are ***,a highly sensitive,simple and rapid new method for the determination of DNA has *** detection limits (3 sigma) are 5.7 ng/mL for ctDNA,7.4 ng/mL for sDNA and 9.2.ng/mLfor hsDNA,*** method can be applied to determination of trace amounts of DNA.

关键词： bleomycinA5, nucleic acids, resonance Rayleigh scattering, fluorescence quenching, absorption spectrum.